Mount Ridley Mines has announced a significant inferred mineral resource of heavy rare earth oxides at its Western Australian project, highlighting strong concentrations of critical elements dysprosium and terbium essential for advanced technologies.
- Inferred Mineral Resource of 122.56 million tonnes at 889 ppm Total Rare Earth Oxides
- Premium 41% heavy rare earth oxide ratio including 4,272 tonnes dysprosium and 719 tonnes terbium
- Resource spans two main zones with shallow, laterally extensive mineralisation
- Rare earths occur alongside scandium and gallium in the same regolith system
- Preliminary metallurgical tests show promising leach recoveries supporting economic extraction potential
A Major Milestone in Rare Earths
Mount Ridley Mines Limited (ASX:MRD) has delivered a landmark update on its Mount Ridley Project in Western Australia, reporting an inferred mineral resource estimate of 122.56 million tonnes at 889 parts per million total rare earth oxides (TREO). This resource notably contains approximately 44,610 tonnes of heavy rare earth oxides (HREO), with a premium 41% HREO to TREO ratio, underscoring the project's rich endowment in critical elements such as dysprosium and terbium.
Strategic Elements for Future Technologies
Dysprosium and terbium are among the most strategically important rare earth elements globally, playing a pivotal role in the manufacture of high-performance permanent magnets used in electric vehicles, wind turbines, and advanced defence technologies. The Mount Ridley Project’s substantial quantities of these elements position it as a potentially vital contributor to the diversification of global supply chains, which are currently heavily concentrated in China.
Geological and Resource Highlights
The resource is divided into two principal zones: Block 1 (Central Zone) with 35.36 million tonnes at 746 ppm TREO, and Block 2 (Northern Zone) with 87.18 million tonnes at 947 ppm TREO. Both zones feature shallow, laterally extensive mineralisation within regolith-hosted systems, amenable to bulk-tonnage open-pit mining methods. Importantly, the rare earth mineralisation occurs within the same regolith profile that hosts significant scandium and gallium resources, reinforcing the project's multi-element critical minerals potential.
Encouraging Metallurgical Testwork
Preliminary metallurgical studies have demonstrated that heavy rare earth elements at Mount Ridley exhibit strong leach responses, with hydrochloric acid leach tests achieving up to 85% recovery of magnet rare earth elements including neodymium, praseodymium, dysprosium, and terbium. This supports the technical feasibility of preferentially recovering higher-value heavy rare earths, a critical factor in the project's economic outlook.
Growth Potential and Strategic Alignment
With more than 80% of the Mount Ridley tenure remaining untested and multiple geophysical target corridors identified, the company plans further resource definition drilling and metallurgical studies to expand and upgrade the mineral resource estimate. The project aligns with recent Australian government initiatives, including the A$1.2 billion Critical Minerals Strategic Reserve, aimed at securing allied supply chains for critical minerals. Mount Ridley Mines is well positioned to contribute to this strategic imperative.
Looking Ahead
Mount Ridley Mines’ Managing Director, Allister Caird, emphasised the significance of the resource update, noting the project's scale, geological continuity, and multi-element nature. The company’s focus remains on delineating high heavy rare earth zones as the primary revenue driver, with scandium and gallium as valuable by-products. Upcoming drilling campaigns and processing research will be closely watched by investors and industry observers alike.
Bottom Line?
Mount Ridley Mines’ heavy rare earth resource positions it as a key player in the evolving critical minerals landscape, but further drilling and metallurgical validation will be crucial to unlock its full potential.
Questions in the middle?
- How will ongoing metallurgical testwork refine recovery rates and processing costs for heavy rare earths?
- What is the timeline and capital requirement for advancing the Mount Ridley Project towards production?
- How might geopolitical shifts and allied supply chain initiatives impact Mount Ridley’s market positioning?